KENNEDY SPACE CENTER, FLA. - -- Space Shuttle Atlantis leaves a billowingclouds of smoke and steam behind just after liftoff from Launch Pad 39B on mission STS-112. Liftoff occurred on time at 3:46 p.m. EDT. Along with a crew of six, Atlantis carries the S1 Integrated Truss Structure and the Crew and Equipment Translation Aid (CETA) Cart A to the International Space Station (ISS). The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss.